Amorphous carbon (a-C) is an important material often used in
microelectronics. Using a recently developed approach, termed Green-Kubo
modal analysis, we were able to calculate the thermal conductivity of
a-C, which yielded excellent agreement with experiments, by employing a
simple correction to the specific heat. The results show that the heat
capacity substantially limits the thermal conductivity of a-C at room
temperature and it is dominated by contributions from diffusons between
10 and 40 THz. Furthermore, the phonon relaxation times in a-C do not
vary significantly with increasing temperature, which is quite unusual
by comparison with the behavior observed for other materials. Published
by AIP Publishing.